Limited Energy Research Articles

Uncovering the connection between obesity and thyroid cancer: the therapeutic potential of adiponectin receptor agonist in the AdipoR2-ULK axis

Adiponectin, a unique adipose-derived factor, is significantly downregulated in obesity, making it a crucial target for tumor-related metabolic research. AdipoRon is a novel adiponectin receptor agonist with the advantages of a small molecular weight, high stability and a long half-life. By screening the cervical adipose tissue of papillary thyroid carcinoma (PTC) patients with adipokine antibody array, we found that adiponectin was a potential correlation factor between obesity and PTC progression. AdipoRon has oral activity and is easily absorbed and delivered to target tissues. The effects of AdipoRon on thyroid cancer have not been reported. In this study, we identified adiponectin receptor 1 (AdipoR1) and AdipoR2 on the surface of thyroid cancer cell lines. AdipoRon inhibited the proliferation and migration of thyroid cancer cells, limited energy metabolism in thyroid cancer cells, promoted differentiation of thyroid cancer cells, and induced autophagy and apoptosis. Mechanistic studies revealed that AdipoRon inhibited p-mTOR Ser2448 and p-p70S6K Thr389, and activated ULK1 and p-ULK1. ULK1 knockdown suppressed the effect of AdipoRon on LC3BII/I protein and lysosomes. AdipoR2 knockdown reduced AdipoRon-induced autophagy in thyroid cancer cells. This study is the first to demonstrate the role of AdipoRon in PTC. Our findings illustrate a previously unknown function and mechanism of the AdipoRon-AdipoR2-ULK/p-ULK1 axis in PTC and lay the foundation for clinical translation of AdipoRon to PTC. Targeting the AdipoRon-AdipoR2-ULK/p-ULK1 axis may represent a new therapeutic strategy for PTC.

ENIAO: Energy Aware Faulty Node Re-Placement Integrated With Duty Cycling and Improved Harmony Search Based Clustering through Adaptive Fish School Search Routing for WSN Optimization

In wireless sensor networks (WSNs), sensor nodes are constrained by resource constraints. The limited energy supply and susceptibility to failure greatly affect WSN lifespan, hindering long-term deployment. ENIAO is an Integrated cross-layer Optimized Routing Approach for WSNs that is fault-tolerant and energy-efficient. A bio-inspired clustering architecture and adaptive duty cycling are incorporated into ENIAO's routing optimization. In a clustering protocol, the network is partitioned, and paths are dynamically optimized within and between clusters. By optimizing active/sleep schedules, duty cycling optimizes energy efficiency. A variety of network conditions have been simulated to assess ENIAO's performance. Regarding fault tolerance and energy consumption, ENIAO significantly prolongs the network lifetime. As compared to benchmark protocols, it achieves higher throughput. As a result of the cross-layer design, ENIAO is automatically adapted to optimize energy usage and routing reliability. In the long run, large-scale IoT deployments are possible with ENIAO due to the integrated approach.

An approximate method of estimating the depth of objects using wavelet-based transformation

Modern three-dimensional computer vision technologies are actively developing, offering new solutions based on the analysis of environmental details. One of the key tasks is to determine the depth of location of objects in images, which requires efficient and fast methods of their processing. This study proposes a new depth estimation method for 3D computer vision based on wavelet transform optimization. Solutions are offered to simplify the disparity calculation, which is traditionally used for the construction of depth maps, with the possibility of describing contours with adjustable detail based on the wavelet transform. The main advantage of this method is the increase in performance due to the allocation of the Haar wavelet carrier length in the extremum search area. The simulation confirmed the effectiveness of the proposed approach for constructing depth maps, which allows us to recommend it for use in unmanned aerial vehicles (UAVs) in conditions of limited computing and energy resources.

Sulfur-vacancy induced asymmetric active site for Bi19S27Br3 nanorods photocatalyzes CO2 conversion to ethylene

The photocatalytic conversion of CO2 into high value-added C2 products remains a significant challenge due to the limited active sites and high energy barrier of C-C coupling process. Herein, the sulfur-vacancy was established on the surface of Bi19S27Br3 nanorods, leading to the electron on residual S atoms become unstable and active. Under the light irradiation, the photoexcited electron transfer from S atoms to neighboring Bi atoms to generate in-situ charge-polarized Bi(3-x)+ asymmetric active sites, which can enhance CO2 adsorption-activation capacity and regulate C-C coupling process for the C1 intermediate. The experimental results and theoretical calculation confirm that more charges aggregate around the induced Bi atoms, reducing the energy barrier of the C-C coupling reaction and improving C2H4 formation. Consequently, the sulfur-vacancy Bi19S27Br3 nanorods achieve efficient C2H4 generation through photocatalytic CO2 reduction, which C2H4 formation rate is 17.80 µmol g−1 after 5-hour photocatalytic reaction, with the product selectivity and electron selectivity of 49 % and 85 %, respectively, outperforming the low sulfur-vacancy Bi19S27Br3 nanorods by four-folds. This research provides new insights into the design of photocatalysts.

FloatingBlue: A Delay Tolerant Networks-Enabled Internet of Things Architecture for Remote Areas Combining Data Mules and Low Power Communications.

Monitoring vast and remote areas like forests using Wireless Sensor Networks (WSNs) presents significant challenges, such as limited energy resources and signal attenuation over long distances due to natural obstacles. Traditional solutions often require extensive infrastructure, which is impractical in such environments. To address these limitations, we introduce the "FloatingBlue" architecture. This architecture, known for its superior energy efficiency, combines Bluetooth Low Energy (BLE) technology with Delay Tolerant Networks (DTN) and data mules. It leverages BLE's low power consumption for energy-efficient sensor broadcasts while utilizing DTN-enabled data mules to collect data from dispersed sensors without constant network connectivity. Deployed in a remote agricultural area in the Amazon region, "FloatingBlue" demonstrated significant improvements in energy efficiency and communication range, with a high Packet Delivery Ratio (PDR). The developed BLE beacon sensor achieved state-of-the-art energy consumption levels, using only 2.25 µJ in sleep mode and 11.8 µJ in transmission mode. Our results highlight "FloatingBlue" as a robust, low-power solution for remote monitoring in challenging environments, offering an energy-efficient and scalable alternative to traditional WSN approaches.

Impressive weight loss induced by a very low-calorie ketogenic diet in a morbidly complex obese patient with a recent episode of acute kidney injury and advanced chronic kidney disease: a case report

The very low-calorie ketogenic diet (VLCKD), characterized by a marked energy restriction that induces rapid weight loss, has recently been proposed as a valid nutritional strategy for managing obesity. VLCKD is commonly considered dangerous for the kidneys due to the misconception that it is high in protein, beyond the risk of electrolyte imbalances and an increase in diuresis. We report a case of safe and effective weight loss induced by VLCKD in a 43-year-old Caucasian woman with a recent episode of acute kidney injury on advanced chronic kidney disease. Surprisingly, we observed that after the diet-induced weight loss, not only did renal function not worsen, but proteinuria also improved. The principal value of this case report is its singular demonstration of impressive weight loss induced by VLCKD in a complex obese patient that was apparently not accompanied by the development of serious adverse sequelae.

An optimized pipeline for high-throughput bulk RNA-Seq deconvolution illustrates the impact of obesity and weight loss on cell composition of human adipose tissue.

Katie Whytock ( Katie.Whytock@adventhealth.com ).

Enhancing energy storage performance of dielectric capacitors: Tailoring CaO-SrO-Na2O-Nb2O5-SiO2 glass-ceramics through controlled crystallization for pulse power applications

As potential dielectric materials for capacitors, glass-ceramics exhibit significant promise in the realm of pulse power supply. Extensive research has been undertaken to explore the commendable voltage resistance and favorable dielectric properties of glass-ceramics. They exhibit a rapid charge and discharge rate. However, the limited energy storage density of glass-ceramics constrains their practical application. In this study, we focused on the preparation of CaO-SrO-Na2O-Nb2O5-SiO2(CSNNS) glass-ceramics through conventional melting and high-temperature crystallization processes. Our investigation delved into the impact of crystallization temperature on the phase composition, dielectric properties, and energy storage characteristics of the CSNNS glass-ceramics. The results indicate a direct correlation between the dielectric constant and dielectric loss, both exhibiting an upward trend with increasing crystallization temperature. Simultaneously, the microstructure of the glass-ceramics manifests signs of deterioration, characterized by larger grain size and heightened porosity, leading to a reduction in breakdown strength. At a crystallization temperature of 1100 °C, the CSNNS glass-ceramics demonstrated a remarkable combination of a high dielectric constant (∼280) and superior breakdown strength (481 kV/cm). The achieved maximum theoretical energy storage density reached 2.87 J/cm3. At an electric field of 100 kV/cm, the effective energy storage density is 0.23 J/cm3, and the energy storage efficiency is 72 %. These findings demonstrate the broad application potential of the CSNNS glass-ceramics in the domain of pulse power, highlighting their relevance for future developments in this field.

Fasting is required for many of the benefits of calorie restriction in the 3xTg mouse model of Alzheimer's disease.

Caloric restriction (CR) is a widely recognized geroprotective intervention that slows or prevents Alzheimer's disease (AD) in animal models. CR is typically implemented via feeding mice a single meal per day; as CR mice rapidly consume their food, they are subject to a prolonged fast between meals. While CR has been shown to improve metabolic and cognitive functions and suppress pathological markers in AD mouse models, the specific contributions of fasting versus calorie reduction remains unclear. Here, we investigated the contribution of fasting and energy restriction to the beneficial effects of CR on AD progression. To test this, we placed 6-month-old 3xTg mice on one of several diet regimens, allowing us to dissect the effects of calories and fasting on metabolism, AD pathology, and cognition. We find that energy restriction alone, without fasting, was sufficient to improve glucose tolerance and reduce adiposity in both sexes, and to reduce Aβ plaques and improve aspects of cognitive performance in females. However, we find that a prolonged fast between meals is necessary for many of the benefits of CR, including improved insulin sensitivity, reduced phosphorylation of tau, decreased neuroinflammation, inhibition of mTORC1 signaling, and activation of autophagy, as well as for the full cognitive benefits of CR. Finally, we find that fasting is essential for the benefits of CR on survival in male 3xTg mice. Overall, our results demonstrate that fasting is required for the full benefits of a CR diet on the development and progression of AD in 3xTg mice, and suggest that both when and how much we eat influences the development and progress of AD.

Effect of Nuts Combined with Energy Restriction on the Obesity Treatment: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Obesity is a multifactorial disease that is difficult to control worldwide. Although nuts are recognized health foods, the application of food in obesity management is unclear. We systematically reviewed the literature and performed a meta-analysis to evaluate if nut consumption favors people on energy restriction (ER) dietary interventions. Four databases were used to search for eligible articles in May 2024. This review was conducted according to the PRISMA guide, and the bias risk of papers was evaluated. For the meta-analysis, we extracted the endpoint values of the group's variables and estimated the effect sizes by the random-effects model. Sixteen and ten articles were included in the systematic review and meta-analysis, respectively. Almonds were evaluated in the majority of studies (n = 6). The consumption of nuts (28 to 84 g/d, 4 to 72 months) included in ER (-250 to 1000 kcal/d) did not differently affect anthropometry (weight loss, BMI, waist and hip circumferences), body composition (fat mass, fat-free mass, or lean mass), markers of glucose (glycemia and insulinemia), lipid metabolism (total cholesterol, HDL-c, LDL-c, LDL-c/HDL-c, or triglycerides), and systolic and diastolic blood pressure. In most analyses, stratifying studies by type of nut or intervention time did not present different results in the meta-analysis. As there are few studies, in addition to great methodological variability, more high-quality trials are needed to confirm these results. The PROSPERO registration number is CRD42023444878.

Electrodialysis with sacrificial magnesium anode for nutrient recovery from primary municipal wastewater: Effect on membrane fouling behaviours

The fertilizer industry is experiencing tremendous stress due to its dependence on limited natural resources and high energy consumption, thus great attention has been paid for alternative nitrogen and phosphorus resources. This study employed electrodialysis (ED) with sacrificial magnesium anode to recover nitrogen and phosphorus (towards struvite formation) from primary municipal wastewater and examined the effects of various operating conditions on ED membranes' fouling behaviour. The results revealed that (1) lowering the concentrate to feed volume (C/F) ratio would reduce overall ED stack resistance, while at a C/F < 0.5, the magnesium corrosion rate decreased with an increase of pH in the concentrate stream; (2) the cation exchange membranes (CEM) adjacent to the feed chamber were more susceptible to foulant depositions (especially organics) than the anion exchange membrane (AEM); the total foulant density was linearly correlated with the increased electrical resistance; (3) increasing current density led to higher ion transport rate, however also promoted membrane fouling for the wastewater containing more solids; (4) the ammonium and phosphate mass transport rates were enhanced by increasing their concentrations in the feed instead of elevating current density. Higher concentrations of nutrient levels in the feed facilitated reduced scaling on membranes, possibly due to more formation of struvite. This study highlights the feasibility of simultaneously treating primary wastewater and recovering nutrients by combining gravity-driven membrane (GDM) filtration with ED.

Experimental investigation and numerical analysis of a hybrid bridge isolation system utilizing bonded and unbonded laminated rubber bearings

To enhance the seismic resilience of bridges equipped with nonseismic laminated rubber bearings, a novel seismic isolation system is proposed, leveraging hybrid bonded and unbonded laminated rubber bearings. An experimental program is conducted to investigate the seismic behavior of this innovative hybrid bearing system. Cyclic loadings are applied to bonded, unbonded, and hybrid bearings to assess their force-displacement hysteretic response, energy dissipation, and restoring performance. The experimental findings reveal that unbonded rubber bearings exhibit significant energy dissipation through sliding but show limitations in restorability. Conversely, bonded bearings demonstrate superior restoring capacity but offer limited energy dissipation. The proposed hybrid bearings, combining bonded and unbonded bearings, achieve a favorable equilibrium between energy dissipation and restoring performance. Compared to individual bonded and unbonded bearings, the hybrid bearings exhibit a remarkable increase in energy dissipation by 110 % and restoring performance by 185 %. Furthermore, a numerical simulation method is proposed to accurately capture the critical hysteretic behavior of the hybrid bearings.

Performance analysis of underwater wireless sensor networks using Reinforcement Learning

This article presents a novel routing protocol named DROR, specifically tailored for underwater wireless sensor networks (UWSNs) to tackle the challenge of void regions. DROR integrates Reinforcement Learning (RL) and Opportunistic Routing (OR) in a recipient-oriented approach, considering the energy limitations and the unique underwater setting. It incorporates a mechanism for void rehabilitation, allowing packets to circumvent void nodes and maintain continuous moving for dependable transmission. Furthermore, a dynamic scheduling strategy based on relative Q-values ensures proficient packet forwarding along the most efficient routing path. Simulation outcomes illustrate the efficacy of the suggested protocol concerning delay, PDR, and energy tax in UWSNs with varying Range, Depths, Packet sizes, and moving radius.

Does brain size of Asiatic toads (Bufo gargarizans) trade-off with other energetically expensive organs along altitudinal gradients?

Abstract Brain size variation is often attributed to energetic trade-offs with other metabolically expensive tissues and organs, which is a prediction of the expensive brain hypothesis (EBH). Here we examine Asiatic toads (Bufo gargarizans) along altitudinal gradients, and test size trade-offs between brain and four visceral organs (heart, liver, alimentary tract, and kidney) with altitude. Body size and scaled mass index (SMI; a proxy for total energy intake) decline with altitude, implying stronger energetic constraints at high altitudes. Relative brain size decreases along altitudinal gradients while visceral organs mostly increase in relative sizes. Using structural equation modelling, a significant negative relationship between brain size and a latent variable ‘budget’, which represents the energy allocation to the four visceral organs, is detected among high-altitudinal toads. Heart appears to have the largest and most consistent response to changes of energy allocation. No such relationships are observed among toads at middle and low altitudes, where high energy intake may allow individuals to forego energetic trade-offs. When applying EBH to poikilotherms, a great emphasis should be placed on total energy intake in addition to energy allocation. Future research on EBH will benefit from more intra-specific comparisons and the evaluation of fitness consequences beyond energy limitation.

Higher fiber higher carbohydrate diets better than lower carbohydrate lower fiber diets for diabetes management: Rapid review with meta-analyses.

Some dietary recommendations continue to recommend carbohydrate restriction as a cornerstone of dietary advice for people with diabetes. We compared the cardiometabolic effects of diets higher in both fiber and carbohydrate with lower carbohydrate lower fiber diets in type 1 or type 2 diabetes. MEDLINE, Embase, and the Cochrane Database of Systematic Reviews up to June 24, 2024, with additional hand searching. Randomized controlled trials in which both dietary fiber and carbohydrate amount had been modified were identified from source evidence syntheses on carbohydrate amount in people with diabetes. Two reviewers independently. Ten eligible trials including 499 participants with diabetes (98% with T2) were identified from the potentially eligible 828 trials included in existing evidence syntheses. Pooled findings indicate that higher fiber higher carbohydrate diets reduced HbA1c (mean difference [MD] -0.50% [95% confidence interval -0.99 to -0.02]), fasting insulin (MD -0.99 μIU/mL [-1.83 to -0.15]), total cholesterol (MD -0.16 mmol/L [-0.27 to -0.05]) and low-density lipoprotein cholesterol (MD -0.16 mmol/L (-0.31 to -0.01) when compared with lower carbohydrate lower fiber diets. Trials with larger differences in fiber and carbohydrate intakes between interventions reported greater reductions. Certainty of evidence for these outcomes was moderate or high, with most outcomes downgraded due to heterogeneity unexplained by any single variable. Our predefined scope excluded trials with co-interventions such as energy restriction, which may have provided addition information. Findings indicate the greater importance of promoting dietary fiber intakes, and the relative unimportance of carbohydrate amount in recommendations for people with diabetes.

Associations between dietary fatty acid and plasma fatty acid composition in non-alcoholic fatty liver disease: secondary analysis from a randomised trial with a hypoenergetic low-carbohydrate high-fat and intermittent fasting diet.

Dietary fatty acids (FA) affect metabolic risk factors. The aim of this study was to explore if changes in dietary fat intake during energy restriction were associated with plasma FA composition. The study also investigated if these changes were associated with changes in liver fat, liver stiffness and plasma lipids among persons with non-alcoholic fatty liver disease. Dietary and plasma FA were investigated in patients with non-alcoholic fatty liver disease (n 48) previously enrolled in a 12-week-long open-label randomised controlled trial comparing two energy-restricted diets: a low-carbohydrate high-fat diet and intermittent fasting diet (5:2), to a control group. Self-reported 3 d food diaries were used for FA intake, and plasma FA composition was analysed using GC. Liver fat content and stiffness were measured by MRI and transient elastography. Changes in intake of total FA (r 0·41; P = 0·005), SFA (r 0·38; P = 0·011) and MUFA (r 0·42; P = 0·004) were associated with changes in liver stiffness. Changes in plasma SFA (r 0·32; P = 0·032) and C16 : 1n-7 (r 0·33; P = 0·028) were positively associated with changes in liver fat, while total n-6 PUFA (r -0·33; P = 0·028) and C20 : 4n-6 (r -0·42; P = 0·005) were inversely associated. Changes in dietary SFA, MUFA, cholesterol and C20:4 were positively associated with plasma total cholesterol and LDL-cholesterol. Modifying the composition of dietary fats during dietary interventions causes changes in the plasma FA profile in patients with non-alcoholic fatty liver disease. These changes are associated with changes in liver fat, stiffness, plasma cholesterol and TAG. Replacing SFA with PUFA may improve metabolic parameters in non-alcoholic fatty liver disease patients during weight loss treatment.

A Distributed Deadlock-Free Task Offloading Algorithm for Integrated Communication–Sensing–Computing Satellites with Data-Dependent Constraints

Integrated communication–sensing–computing (ICSC) satellites, which integrate edge computing servers on Earth observation satellites to process collected data directly in orbit, are attracting growing attention. Nevertheless, some monitoring tasks involve sequential sub-tasks like target observation and movement prediction, leading to data dependencies. Moreover, the limited energy supply on satellites requires the sequential execution of sub-tasks. Therefore, inappropriate assignments can cause circular waiting among satellites, resulting in deadlocks. This paper formulates task offloading in ICSC satellites with data-dependent constraints as a mixed-integer linear programming (MILP) problem, aiming to minimize service latency and energy consumption simultaneously. Given the non-centrality of ICSC satellites, we propose a distributed deadlock-free task offloading (DDFTO) algorithm. DDFTO operates in parallel on each satellite, alternating between sub-task inclusion and consensus and sub-task removal until a common offloading assignment is reached. To avoid deadlocks arising from sub-task inclusion, we introduce the deadlock-free insertion mechanism (DFIM), which strategically restricts the insertion positions of sub-tasks based on interval relationships, ensuring deadlock-free assignments. Extensive experiments demonstrate the effectiveness of DFIM in avoiding deadlocks and show that the DDFTO algorithm outperforms benchmark algorithms in achieving deadlock-free offloading assignments.

A new electrolyte for molten carbonate decarbonization

The molten Li2CO3 transformation of CO2 to oxygen and graphene nanocarbons (GNCs), such as carbon nanotubes, is a large scale process of CO2 removal to mitigate climate change. Sustainability benefits include the stability and storage of the products, and the GNC product value is an incentive for carbon removal. However, high Li2CO3 cost and its competitive use as the primary raw material for EV batteries are obstacles. Common alternative alkali or alkali earth carbonates are ineffective substitutes due to impure GNC products or high energy limitations. A new decarbonization chemistry utilizing a majority of SrCO3 is investigated. SrCO3 is much more abundant, and an order of magnitude less expensive, than Li2CO3. The equivalent affinities of SrCO3 and Li2CO3 for absorbing and releasing CO2 are demonstrated to be comparable, and are unlike all the other alkali and alkali earth carbonates. The temperature domain in which the CO2 transformation to GNCs can be effective is <800 °C. Although the solidus temperature of SrCO3 is 1494 °C, it is remarkably soluble in Li2CO3 at temperatures less than 800 °C, and the electrolysis energy is low. High purity CNTs are synthesized from CO2 respectively in SrCO3 based electrolytes containing 30% or less Li2CO3.

Single elemental planar light concentrator using skewed V-groove optics

Light concentrators are widely used to address the challenges of solar radiation's limited energy density. However, traditional light concentrators suffer from bulkiness, higher focal length, low solar acceptance, and cost factor due to the usage of large imaging optics elements. Waveguide-based planar light concentrators (PLC) have been engineered as a solution to these challenges. They work by collecting light at the incident face and channeling it to the lateral face of the waveguides. However, the existing PLC designs mostly consist of multiple optics elements, resulting in the need for precise positioning and point-to-point solar tracking. Addressing these complexities, a new design for waveguide-based PLC is presented. It features a simplified array of skewed V-grooves within an optical slab, essentially creating a single elemental optics. This novel skewed V-groove-based PLC (SV-PLC) introduces a low-concentration (i.e., <10X geometric concentration (GC)) solution that offers high angular acceptance along one axis. The current study aims to establish the novel design concept, validate, optimize, and assess the design through the Ray-tracing simulation. Further, based on the simulation results, a functional prototype was successfully fabricated in PMMA using laser machining. The results of the optical characterization of the SV-PLC showed that the Optical Efficiency (OE) was approximately around half the theoretical OE. Angular-dependent ray trace results showed a lower OE drop (<10 %) for incident angles less than 15°, and a maximum drop of 30 % (for a 10X GC design) for an incident angle of 23.5° (i.e., half the angle shift of the sun through seasons).

Torpor energetics are related to the interaction between body mass and climate in bats of the family Vespertilionidae.

Torpor is an adaptive strategy allowing heterothermic animals to cope with energy limitations. In birds and mammals, intrinsic and extrinsic factors, such as body mass and ambient temperature, are the main variables influencing torpor use. Speakman and Thomas (2003) proposed a theoretical model of the relationship between the metabolic rate during torpor and the ambient temperature. Nevertheless, no empirical attempts have been made to assess the model predictions under different climates. Using open-flow respirometry, we evaluated the ambient temperature at which bats entered torpor and when torpid metabolic rate reached its minimum, the reduction in metabolic rate below basal values, and minimum torpid metabolic rate in 11 bat species of the family Vespertilionidae with different body mass from warm and cold climates. We included data on the minimum torpid metabolic rate of five species we retrieved from the literature. We tested the effects using mixed-effect phylogenetic models. All models showed a significant interaction between body mass and climate. Smaller bats went into torpor and reached minimum torpid metabolic rates at warmer temperatures, showed a higher reduction in the metabolic rate below basal values, and presented lower torpid metabolic rates than larger ones. The slopes of the models were different for bats from different climates. These results are likely explained by differences in body mass and the metabolic rate of bats, which may favor larger bats expressing torpor in colder sites and smaller bats in the warmer ones. Further studies to assess torpor use in bats of different climates are proposed.